Manatee is a web-based tool used to perform manual functional annotation. It has been specifically designed to optimize the ability of curators to evaluate all available sequence-based and experimental data to assign the best possible annotation to a given gene product.
Manatee allows users to view, modify, and store annotation through interactions with an underlying relational database where all of the information is stored. Manatee supports the storage of multiple types of functional annotation including protein names, gene symbols, EC numbers, Gene Ontology terms, and associated supporting evidence. In addition, Manatee provides summary views of statistics and information from the genome as a whole.

Manatee was originally developed at The Institute for Genome Sciences.
Continuing development of Manatee is ongoing at both the J. Craig Venter Institute (JCVI, into which TIGR was merged) and the Institute for Genomes Sciences (IGS) at the University of Maryland School of Medicine.
Development of Manatee has split into two branches: one using the relational schema developed in-house at TIGR for the storage of information (at JCVI) and one using the GMOD-developed chado schema (at IGS).